This invention relates in general to the packaging art, and is more particularly concerned with reclosable bags.
Numerous and varied reclosable bag structures have been proposed, and some have proven to be commercially quite good.
In particular, there has been some emphasis on providing tamper evident bags, and bags that are hermetically sealed until they are opened for access to the contents, whereafter a reclosable fastener device comes into play for maintaining the contents within the bag until access is again desired. By way of example, attention is directed to the following U.S. Patents as representative of various approaches to the type of bag with which the present invention relates by way of improvement:
U.S. Pat. Nos. 2,978,769 and 3,172,443 disclose non-reclosable frangible connections of fastener profiles.
U.S. Pat. No. 3,325,084 discloses a closure flap provided with closure profiles that will meet with closure profiles o the front of the bag or package.
U.S. Pat. No. 3,326,399 discloses the use of magnetic reclosable fastening means.
U.S. Pat. Nos. 3,198,288; 3,473,589 and 3,780,781 disclose reclosable profile fasteners or zippers, and a tear off top on the bag for access to the zipper.
U.S. Pat. No. 3,543,343 discloses a bag with reclosable fastener profiles and a tear cord for opening the bag.
U.S. Pat. No. 3,625,270, discloses a tear ribbon device for opening the bag.
U.S. Pat. No. 3,746,215, discloses a funnel arrangement which retains the bag sealed closed until the funnel is everted and the end snipped off.
U.S. Pat. Nos. 3,991,801; 4,191,230 and 4,235,653, disclose other arrangements of funnel bags.
U.S. Pat. No. 4,241,865, discloses a heavy duty bag to be made from paper and equipped with a primary rip cord closure and a hood thereover provided with a reclosable zipper of the interlocking teeth type.
In spite of the fairly high state of development in this art, there is still room for improvement and the attainment of simplicity and economy in dual fastener bags, that is, bags that have hermetic or at least tamper evident non-reclosable closure means and associated reclosable zippers.